CVE-2016-0701

Severity: low (CVSS 3.7 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 83.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-02-15 · updated 2026-06-17
Weakness: CWE-200

Description

The DH_check_pub_key function in crypto/dh/dh_check.c in OpenSSL 1.0.2 before 1.0.2f does not ensure that prime numbers are appropriate for Diffie-Hellman (DH) key exchange, which makes it easier for remote attackers to discover a private DH exponent by making multiple handshakes with a peer that chose an inappropriate number, as demonstrated by a number in an X9.42 file.

Affected products

OpenSSL: 1.0.2, 1.0.2-beta1, 1.0.2-beta2, 1.0.2-beta3, 1.0.2a, 1.0.2b (+3)

References

http://intothesymmetry.blogspot.com/2016/01/openssl-key-recovery-attack-on-dh-small.html
http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759
http://lists.fedoraproject.org/pipermail/package-announce/2016-January/176373.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00009.html
http://www.openssl.org/news/secadv/20160128.txt
http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html
http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
http://www.securityfocus.com/bid/82233
http://www.securityfocus.com/bid/91787
http://www.securitytracker.com/id/1034849
http://www.ubuntu.com/usn/USN-2883-1
https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf

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